Balanced to G2.5 25000rpm High Precision: TIR 2μm or 0.0001" Bore Diameter: 1/4 " Gage length: 3.5" For All CAT40 Spindles For all CAT40 Spindle Tool Holder, High precision, cost-effective, USA quality. Advantages of shrink tool holders: 1. Fast loading and unloading of tools, using heat shrinking machine to heat, 13KW high power can complete the tool installation and clamp within 5 seconds, cooling only 30 seconds, the unique water cooling device can prevent the accuracy of the tool holder from deteriorating. 2. High precision and small runout. The tool installation part does not have components such as nuts and collets required by collet chucks, simple and effective, cold shrinkage clamping is strong and stable, tool deflection ≤3μ, reducing tool wear and ensuring high precision during high-speed machining. 3. The crown is small and widely used. The ultra-thin tip part and abundant tool holder shape changes can be widely used in high-speed, high-precision machining and deep hole machining. 4. Simple and efficient, long life. Hot loading and unloading operation, even if the same tool holder is hot loading and unloading more than 2000 times, there will be no change in accuracy, stable performance, and long service life. The weakness of shrink tool holders: 1. Need to buy a heat shrink machine, thousands to tens of thousands are available. 2. After thousands of times of use, when the oxide layer is peeled off, the accuracy is not so high.